矿物定向排列致各向异性岩石渐进破坏强度特征——以黑云母石英片岩为例  

Progressive failure strength characteristics of anisotropic rocks caused by mineral directional arrangement:a case of biotite quartz schist

作　　者：包含[1] 陈志洋 兰恒星[2] 裴润生 伍法权 晏长根[1] 陶悦[1] BAO Han;CHEN Zhi-yang;LAN Heng-xing;PEI Run-sheng;WU Fa-quan;YAN Chang-gen;TAO Yue(School of Highway,Chang’an University,Xi’an,Shaanxi 710064,China;Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;School of Civil Engineering,Shaoxing University,Shaoxing,Zhejiang 312000,China)

机构地区：[1]长安大学公路学院,陕西西安710064 [2]中国科学院地理科学与资源研究所,北京100101 [3]绍兴文理学院土木工程学院,浙江绍兴312000

出　　处：《岩土力学》2022年第8期2060-2070,共11页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.42177142,No.41927806,No.42041006);西安市科协青年人才托举计划(No.095920201310);长安大学中央高校基本科研业务费专项资金(No.300102212213)。

摘　　要：为探究矿物定向排列致各向异性岩石的渐进破坏强度特征,以黑云母石英片岩为例,针对含0°、45°、90°3种片理角度的试样开展三轴压缩试验,分析了试样的宏微观破坏特征及渐进破坏力学强度指标,探讨了与其他类型各向异性岩石的差异性。结果表明:岩石的破坏特征与其片理结构密切相关,片理面角度从0°增大到90°,试样的宏微观破裂特征由以张拉为主向剪切为主再向张剪并存为主转变;岩石强度特征值表现出显著的各向异性,随着片理面角度的增大,围压升高所产生的强度特征值增强效应减弱,但强度值变化却呈加速增大趋势;强度特征值比的各向异性变化规律并不明显,在高围压下,强度特征值比的各向异性逐渐减弱乃至消失。矿物定向排列岩石与含层理结构岩石的破坏形式、强度特征值及其比值的表现规律均有所不同,深入了解矿物定向排列岩石的力学特性将有助于指导相关工程实践活动。To explore the strength characteristics of anisotropic rocks caused by mineral directional arrangement during progressive failure process,biotite quartz schist was taken as an example,and triaxial compression tests were carried out on samples with schistosity angles of 0°,45° and 90°.The macro and micro failure characteristics and progressive failure strength index of the specimens were analyzed,and the differences with other types of anisotropic rock were discussed.The results show that the failure characteristics of biotite quartz schist are closely related to its schistosity.With the schistosity angle increasing from 0° to 90°,the main macro and micro fracture modes of the specimens change from tensile to shear,and then to co-existence of tensile and shear.The strength characteristic values of biotite quartz schist show significant anisotropy.With the increase of schistosity angle,the strengthening effect caused by confining pressure increase on the strength characteristic values weakens,but the change of the strength value has a trend of acceleration.The anisotropic variation law of the ratio of strength characteristic value is not obvious,which gradually weakens and even disappears under high confining pressure.The fracture modes,variations of strength characteristic values and their ratios of anisotropic rocks with directional arrangement of minerals are different from those of rocks with stratified structure.A thorough understanding of the mechanical properties of rocks with directional arrangement of minerals will be helpful to guide the related engineering practice.

关 键 词：矿物定向排列 黑云母石英片岩 渐进破坏 强度特征值 各向异性 

分 类 号：TU457[建筑科学—岩土工程]